A message on the Ubuntu devel mailing list mentions that the current state of Unity will be brought up for discussion and if needed, the Classic GNOME Desktop may be default after all in Ubuntu 11.04:

* Classic Gnome Desktop by default (dmandell)
* Action: rickspencer3 will bring up the state of unity on the -desktop list for public review and discussion

The reason for this are some feature regressions like usability issues: settings are hard to find, the launcher icons behavior but most importantly, the buggy state in which Unity / Compiz is at this stage.

And indeed, a thread (see here - search for "Default Desktop Experience for 11.04") has been started and everyone is expressing his opinion regarding the current Unity state. For now, most people seem to agree that Unity should be default in 11.04:

I can honestly say that when I am not in a unity environment, I don't feel at home. I bounce back and forth between ubuntu and osx, and when nvidia was broken, and when I'm in osx, I often find myself trying to 4 finger slide, throwing my mouse to 0,0, tapping super, and generally evoking unity idioms. unity has very quickly made itself a *very* natural part of my workflow and i couldn't imagine working without it any more.

- Alex Launi

While Unity does feel alpha, I don't think any missing features / usability will stay in its way of becoming default in Ubuntu 11.04. The crashes however are quite a serious issue and while Unity is a lot more stable lately, the crashes do happen every few minutes on my netbook (I didn't upgrade my desktop to 11.04 yet).

Being so late (Ubuntu 11.04 will be released in less then a month) makes all this very hard to predict: it's probably too late to fix all the bugs but also too late to switch back to the Classic GNOME Desktop. Or is it?